JP3067516B2 - Transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission capable of increasing the amount of engagement between a pinion and rack teeth.

[0002]

2. Description of the Related Art A transmission proposed by the present inventor in Japanese Patent Publication No. 37-5462, for example, as shown in FIG. 22, is provided with a rotatable driven case a and a rotation center line parallel to the driven case a. A drive shaft c that is movably supported by the deflection means b in a direction orthogonal to the rotation center line.
And

The driven case a has two pairs of rails d1, d1, d2, d2 which face each other on both sides of the rotation center line and extend in a plane which is parallel and orthogonal to the rotation center line. Intersecting lines r1 and r2 parallel to the rails d1 and d2 and intersecting with the rotation center line of the driven case are clearly shown in FIG.
Thus , the slide frames e and f are movably mounted between the rail portions while intersecting each other at right angles, that is, at an angle of 90 ° .

The slide frames e and f form an opening g having two inner sides facing inward, and a rack tooth h and a cam surface i parallel to the rack teeth are arranged on each of the facing inner sides. .

The drive shaft c is provided with slide frames e and f.
When fixing a pair of pinions j that can mesh with the rack teeth h
A cam plate both of which are in contact with the facing cam surface i
k is eccentrically held to be rotatable.

[0006] The deflection means b comprises a screw shaft m and a screw shaft m.
And a slide plate p whose rotation is restricted by a slide shaft o, and a drive shaft c is rotatably supported on the slide plate p. A pin n for preventing rotation of the cam plate k is attached to the sliding plate p.

In this transmission, however, the cam plate k of the drive shaft c is mounted on the cam surfaces of the slide frames e and f, and the pinions j and j.
Are engaged with one rack tooth h of each pair of rack teeth facing each other, so that the slide frames e and f are moved with the movement of the rack teeth h meshing with the pinion j, and the rail portion d1 is moved. , D1, d2, and d2 to transmit torque to rotate the driven case a.

At this time, the cam k moves the rack teeth h of the slide frames e and f along a locus passing near the pitch circle of the virtual internal gear meshing with the rack teeth h and the pinion j. Useful. Further, the position of the pinion j is changed by rotating the screw shaft m of the deflection means b, and the cam k moves the rack tooth h at the changed position, that is, on a pitch circle having a different radius.

[0009]

However, in the above-mentioned prior art, a disc cam is used as the cam plate k, and the rail portions d1 and d2 intersect at an angle of 90 ° with each other.
Is used, there is a problem that the amount of engagement between the rack teeth h and the pinion j is small and rotation unevenness occurs, so that torque is not smoothly transmitted.

According to the present invention, the rail section is formed at an angle of 120 °.
It is another object of the present invention to provide a transmission that can solve the above-described problem based on a pair of cam plates and a cam plate that is formed into an oval shape.

[0011]

According to the present invention, there is provided a driven case rotatably supported by a stationary member, a driven case disposed parallel to a rotation center line of the driven case, and orthogonal to the rotation center line by using displacement means. And a driven shaft movably supported in the direction of rotation, and the driven case is provided with a plurality of pairs of rails extending in a plane parallel to each other on both sides of the rotation center line and perpendicular to the rotation center line. Provided side by side in the direction of the rotation center line, and the intersection lines that are parallel to the rails arranged in the direction of the rotation center line and intersect with the rotation center line intersect at an equal angle with each other, and between the facing rail portions, By being guided, each slide frame is moved in a direction orthogonal to the rotation center line and at an equal angle, and further provided with slide frames each having an opening having two opposed inner sides, and each of the slide frames is aligned with each other. While the rack teeth and the cam surface parallel to the pitch line of the rack teeth are provided side by side on the inner side, the rack teeth on one inner side that rotates integrally with the drive shaft and faces the slide frame are provided on the drive shaft. By guiding the slide frame by contacting the meshable pinion and the cam surface on the inner side of each slide frame facing each other, the rack teeth meshing with the pinion are turned into a virtual internal gear pitch circle whose rack teeth mesh with the pinion. A cam plate that moves along a locus similar to that of the above, wherein the rail portion is arranged with three pairs of the intersection lines intersecting at an angle of 120 ° arranged in the direction of the rotation center line, and the cam plate is , An arc R1 and an arc R2 having a radius larger than that of the arc R1 are combined to form an omsby-shaped contour having the same length across the outer periphery, and the pinion is Cam plate arc R
1 is a transmission device characterized in that the transmission device is decentered toward the center of the radius of No. 1.

[0012]

By providing three pairs of rail portions at an angle of 120 °, at least one pair of engagement between the rack teeth and the pinion can be ensured during the rotation of the driven case by 60 °. The amount of engagement can be large.

The rack teeth extend from the large-diameter arc R2 of the oval-shaped cam plate to the large-diameter arc R2 through the small-diameter arc R1 of the cam plate.
Ru is guided in parallel to the lines moving locus in contact with each arc. Like this , the rack teeth and the pinion start to mesh early,
In addition, the end of meshing can be delayed, and the meshing amount per pair of meshing of the rack teeth and the pinion, that is, the meshing angle range can be increased.

[0014] Further in rats started meshing circumferential speed of the click teeth of the rack teeth and the pinion by approaching the peripheral speed of the pinion, and smooth Noriutsuri engagement end.

[0015]

An embodiment of the present invention will be described below with reference to the drawings. The transmission 1 of the present invention includes a driven case 2 rotatably supported by a stationary member S, and a driven case 2 that is disposed parallel to the rotation center line CL of the driven case 2 and is biased in a direction orthogonal to the rotation center line CL. Drive shaft 4 that is movably supported using the positioning means 3
In this embodiment, the transmission 1 is attached to the vehicle body of the bicycle M by a stationary member S as shown in FIG. 21, and is used as a transmission forming a part of the rear wheel 32.

In this embodiment, the crank arm torque given by the petal P of the bicycle M gives a rotational torque that rotates the input cylinder 20 shown in FIG. 1 clockwise as viewed from above. (In this example, the clockwise direction and the counterclockwise direction mean a clockwise direction and a counterclockwise direction about the rotation center line CL as viewed from above in FIG. 1).

The driven case 2 comprises a cylindrical portion 2A having a cylindrical shape in the present embodiment, and disk-shaped lid portions 2B and 2C for closing both ends of the cylindrical portion 2A. A pair of brim portions 2D orbiting the outer peripheral surface are formed.

In this embodiment, the stationary member S is
The driven case 2 has fixed shafts 29 on both sides fixed to the vehicle body F of the bicycle M, and the driven case 2 has an input cylinder 20 as input means rotatably extrapolated to one fixed shaft 29 on the lid 2B.
Are rotatably supported around a rotation center line CL. A brake drum BD is fixed to the other cover 2C, and is rotatably supported by the other fixed shaft 29.

A rim and a pneumatic tire are mounted on the collar portion 2D via a plurality of spokes 31, respectively, to constitute a rear wheel 32 of the bicycle.

As shown in FIGS. 1 and 6, the driven case 2 has three pairs of rails 5a to 5a extending parallel to each other on both sides of the rotation center line CL and extending in a plane perpendicular to the rotation center line CL. 5c are arranged in the direction of the rotation center line CL.

In the present embodiment, the rail portion 5 includes a rail fitting 15 having a bent piece 14 which is bent integrally and at a right angle with a linear portion of an arc piece 16 having the same diameter as the inner peripheral surface of the cylindrical portion 2A. The rail portion 5 is formed by facing the bent pieces 14 of the rail fitting 15 in parallel with each other.

The lines of intersection parallel to the rails 5 arranged in the direction of the rotation center line and intersecting the rotation center line are at equal angles to each other. As will be described later, in the present invention employing three pairs of rails 5a, 5b, and 5c, by using an omsby-shaped cam plate 13, the intersection is positioned so as to intersect at an angle of 120 °. Also, rail brackets 15, 1
5 are bolted together at the same angle and in the direction of the rotation center line by using a spacer T2 and six mounting portions T1 provided at equal pitches of 60 degrees on the inner peripheral surface of the cylindrical portion 2A. You.

Further, each of the rail portions 5a to 5c has
A slide frame 9 which is guided and moved by the rail portion 5 in a direction orthogonal to the rotation center line CL is provided.

As shown in FIG. 6, in this embodiment, the slide frame 9 includes a pair of frame plates 33, 34, and rollers 35 pivotally supported at four corners between the frame plates 33, 34.
5 rolls on the rails 5a to 5c.

Each of the frame plates 33 and 34 has a hollow opening 6 formed therein, and each of the inner sides 7 of the opening 6 which face each other in a direction orthogonal to the rails 5 has the inner side. 7
Each rack tooth 10 having a pitch line parallel to the rack teeth 10 and facing each other is provided, and a cam surface 11 parallel to the rack teeth 10 is formed by the inner side 7.

In the present embodiment, the rack teeth 10 form a pair of left and right projections 37 projecting up and down.
7 is inserted into the oblique groove 39 formed in each of the frame plates 33 and 34, and is slidably supported diagonally. This inclined groove 39
An angle of 60 to 85 ° with respect to the pitch line of the rack teeth 10 in a direction in which the outer end farther from the inner end than the inner end on the rack tooth 10 side is located in a counterclockwise position relative to the inner end It is inclined to make it. For this reason, escape during power transmission is reduced, and power loss is reduced. Escape during power transmission is reduced to reduce power loss.

When the petal is stopped (ie, the pinions 12A to 12C are stopped), such as when the bicycle M goes down a hill, and the slide frame 9 is driven from the driven case 2 by the rear wheels, the rack teeth 10 By the inclined groove 39 having the predetermined direction, when meshing with the pinions 12A to 12C, it is possible to smoothly pull in and escape in the direction of the inclined groove 39, and the so-called rack teeth 10 function as a ratchet.

The rack teeth 10 are constantly urged in a direction approaching each other by a spring 41 that circulates around a groove 40 formed in the rack teeth, and the tooth tips protrude inward from the cam surface 11.

The pitch line of the rack teeth 10 and the cam surface 11 can be set at the same height, or can be close to the tooth tip or root.

Further, each frame plate 33, 34 of the slide frame 9
Is formed by forming an outer peripheral surface portion on the side orthogonal to the rail portion 5 with an arc portion having the same diameter as the inner peripheral surface of the driven case 2 and also forming a cutout circular portion 36, and the mounting portion T1 (FIG. 6) is prevented.

The slide frame 9 has the rail 5
On the side, a projecting portion 42 that covers the bent piece 14 of the rail portion 5 from above and below is formed, and each slide frame 9 is not detached from each of the rail portions 5, and furthermore, by providing the roller 35, The moving direction can be changed smoothly and surely by 120 ° with respect to the rail portion 5.

As shown in FIGS. 1 to 4 and FIGS. 7 to 12, the deflection means 3 is provided with the input cylinder 20 as an input means.
In the present embodiment, a rotary frame 22 that supports a counter gear 21 and a swing arm 23 as a transmission unit that can transmit power between the input cylinder 20 and the drive shaft 4 are included.

In this embodiment, the input cylinder 20 has a fixed shaft 29.
The input end is directly supported by the fixed shaft 29 via a bearing via a bearing.

As shown in FIG. 7, the clutch case 110 comprises a cylindrical portion 111 and a flange 112. The one-way clutch 30 is further accommodated in the cylindrical portion 111 between the cylindrical portion 111 and the fixed shaft 29. , This fixed shaft 29
On the other hand, only one direction, in this example, clockwise, is allowed to rotate, and the pivot 112 is supported.
By being fixed to the outer cover 46 on the input side 2, the rotating frame 22 can rotate only clockwise around the fixed shaft 29 .

The input cylinder 20 has a sprocket 43 at one end exposed to the outside of the driven case 2, and the other end faces the inside of the driven case 2 and, as shown in FIG. A gear portion 45 that can be engaged with the counter gear 21 by appearing at the notch portion 46A provided in the boss portion 46B is provided.

The rotating frame 22 is provided with an outer cover 46 and an inner cover 47 which are externally inserted into the input
9 and the like.

The outer lid 46 is rotatable with the input cylinder 20.
That is, a substantially disk-shaped substrate portion is provided around the cylindrical portion supported via an appropriate bearing on the outer peripheral surface of the input cylinder 20 so that the input cylinder 20 is rotatable. The flange 112 of the clutch case 110 is fixed to the cylindrical portion.

As shown in FIG. 4, the inner cover 47 is formed of an annular body 59 forming an opening circular portion 60 therein, and the pin 49 implanted in the annular body 59 causes the swing arm 2 to rotate.
The third boss 57 is pivotally supported. The boss portion 57 pivotally supports the counter gear 21.

The inner lid 47 has an engaging projection 61 on the side of the opening circle 60 and an engaging recess 62 having an arc surface 62A centered on the pin 49 on the outer periphery.

Further, as shown in FIG.
The boss portion 57 which is externally inserted into the pin 49 and is pivotally supported is provided at a substantially intermediate position of the long-axis arm 53, and a receiving cylinder which can pivotally support the driving shaft 4 at one end thereof. A portion 54 is formed, and an engagement pin 56 projects from the other end. The engagement pin 56 engages with the engagement recess 62 to determine an initial position of the swing arm 23 with respect to the rotary frame 22.

The gear portion 24 is formed in the receiving cylinder portion 54 in a substantially fan-like shape with the boss portion 57 as a center. The boss portion 57 and the cylinder portion 54 are parallel to the rotation center line CL, so that the drive shaft 4 is arranged parallel to the rotation center line CL of the driven case 2.

As shown in FIG. 7, the counter gear 21 includes a first gear portion 51 and a second gear portion 5 which mesh with the gear portion 45 of the input cylinder 20 and the drive gear 50 of the drive shaft 4, respectively.
2 are integrally provided on the same axis.

In the present embodiment, the swing arm 23 is moved by a gear portion 24 as shown in FIGS.
Returning side by the spring means 25 shown in FIG.
2 is urged toward the side where the engagement pin 56 is engaged.

In this embodiment, the spring means 25 is provided with the outer cover 4.
A conston spring 26 composed of a spiral spring one end of which is fixed to a spring case 82 fixed to 6; a winding shaft 74 having a thread groove 75 for winding a small-diameter wire fixed to the other end of the conston spring 26; A speed increasing portion 77 capable of increasing the speed of rotation of the meshing gear 66 meshing with the gear portion 24 of the swing arm 23 and transmitting the rotation to the winding shaft 74.

The conston spring 26 is a constant-load spiral spring formed with a constant curvature in a no-load free state, and can exert a constant restoring force regardless of the amount of unwinding from the spring case 82.

One end of the wire is provided between the outer lid 46 and the inner lid 47 on the same circumference as the guide roller body 8 which is pivotally supported.
3 and is attached to the winding shaft 74.

The take-up shaft 74 is pivotally supported by the rotating frame 22 and has a thread groove 75 around it.
A winding pinion 73 is provided integrally with the wire 4, and the wire is wound around the screw groove while the conston spring 26 is unwound from the spring case 82 by the rotation thereof.

As shown in FIG. 9, the speed increasing portion 77 includes a meshing gear 66 meshing with the gear portion 24 of the swing arm 23, a pinion 67 meshing with the gear 66, and a gear 6 integral therewith.
8 and a final take-up pinion 73. In this example,
The speed from the gear portion 24 of the swing arm 23 to the winding pinion 73 is increased 120 times, and the slight deflection angle of the sliding arm 23 is increased 120 times. Thus, the speed increasing portion 77 also functions as a resistance of the swing arm 23, and buffers a sudden return operation of the swing arm 23.

In this embodiment, the winding pinion 73 of the winding shaft 74 is rotated at an increased speed, so that the minute swing of the swing arm 23 is also increased, and the winding pinion 73 is rotated. 73 can be rotated.

The engaging pin 56 of the swing arm 23 is
Further extending downward, as shown in FIG. 4, it is loosely inserted into an elongated hole 99 formed in the projecting piece 97 of the annular auxiliary plate 27 rotatably attached to the inner lid 47.

The auxiliary plate 27 is provided with an annular projection 9 which is rotatable concentrically by engaging with the annular groove 63 of the inner lid 47.
A guide frame 100 for forming a substantially rectangular opening 101 is provided in an annular body 95 having a 6.

The guide frame 100 is composed of guide pieces 102 facing and parallel to each other, and arc pieces 103 at both ends thereof. The arc pieces 103 are substantially equal to the inner diameter of the opening circular portion 60 of the inner lid 47. It can rotate inside.
The guide pieces 102, 102 of the opening 101 guide the bulging portion 92 (shown in FIG. 5) provided on the cam plate 13 to be attached to the drive shaft 4, and thus can guide the movement of the drive shaft 4.

The drive shaft 4 is, for example, a spline shaft as shown in FIG. 3, and includes a drive gear 50 and three pinions 12A, 12B, 12 having a boss 86 in this embodiment.
C (shown in FIG. 5) is fixed so that relative rotation is impossible, and the cam plates 13A to 13D are rotatably supported by the boss portion 86 thereof.

As shown in FIGS. 5 and 10, in the present embodiment, the cam plates 13A to 13D have a tapered outline in which the length H sandwiching the outer periphery is always equal.
The radius of curvature is R from each top of the reference equilateral triangle.
1. An arc of 60 degrees is drawn at R2 (R1 <R2), and these are sequentially formed as an outline. The curvature radius R1
Are approximated to the pitch circle radii of the pinions 12A. The total length R1 + R2 is made equal to the distance between the cam surfaces 11, 11 of the slide frame 9.

In the present embodiment, as shown in FIG. 5, the cam plates 13A to 13D have a shaft hole 8 centered on one vertex of the equilateral triangle as a reference of the contour of the cam plates 13A to 13D.
7 are formed. The cam plate 13A is supported by the drive shaft 4 via the cylinder portion 54 of the swing arm 23, and the boss portion 86 of the pinion 12B, 12C has this shaft hole 8 formed therein.
7 is inserted. The cam plate 13D is supported by the drive shaft 4 via a bearing 93.

Therefore, the slide frame 9 capable of moving the rail portion 5 with the rotation of the driven case 2 is mounted on the cam plate 13.
16 and 20, the rack teeth 10 meshing with the pinion 12 move along with the movement of the rack teeth 10 approximating the virtual internal gear pitch circle meshing with the pinion 12, as shown in FIGS. The pinion 12 and the rack teeth 10 can be sequentially engaged.

At this time, as described above, the cam plate 13 has a shape of three small-diameter portions having a radius R1 and three large-diameter portions having a radius R2. The pitch radius of the pinion 12 is approximated to the radius R1, and the pinion is made to coincide with the center of the radius R1. The slide frame 9 has its cam surface 1
1 is in contact with the contour surface 91 of the cam plate,
Also moves along a movement locus that keeps the direction parallel to the tangent to the contour surface 91. That is, in the case of the cam plate 13 in the shape of a boss, the radius R
2 of movement trajectory and ing from the large-diameter arc through while in contact with the large diameter arc of radius R2 to fart a small arc having a radius R1. This allows
In addition, it is possible to smoothly transfer the gear from the rack tooth to the next rack tooth and reduce uneven rotation.

Each of the cam plates 13A to 13D has a hole 89 formed at the same position, and a bolt 90 penetrating through the hole 89 is provided. 91 are aligned and fixed together.

Further, the cam plates 13A and 13D have the same shape in which both ends of an eccentric flat surface 92A which bulges up and down and which are parallel to each other with the axis of the drive shaft 4 symmetrically interposed therebetween are connected by an arc surface 92B. The above-mentioned bulging portion 92 is provided.

The bulging portion 92 of the cam plate 13A is connected to the guide piece 1 of the guide frame 100 of the auxiliary plate 27 shown in FIG.
The drive shaft 4 can be moved within a predetermined range along the guide piece 102 by supporting the eccentric planes 92A, 92A between the guide pieces 102, 102.

The bulging portion 92 of the cam plate 13D is connected to the mounting plate 17 pivotally supported by the lid 2C as shown in FIG.
Are movably supported by a similar guide frame 104.

The mounting plate 17 is, like the guide frame 100 of the auxiliary plate 27, provided with the guide pieces 10 facing in parallel with each other.
5 and the arc piece 106, a cavity 109 is formed therein, and the bulging portion 92 of the cam plate 13D is supported in the cavity 109 so as to be able to move linearly.

As described above, the bulging portion 92 of the upper cam plate 13A
Between the guide pieces 102 of the auxiliary plate 27 and the bulging portion 92 of the lower cam plate 13B
The drive shaft 4 is slidably supported between the drive case 2 and the drive shaft 4. The drive shaft 4 is parallel to the rotation center line of the driven case 2. 4 can be moved to change its axial center.

The shaft hole 107 of the cylindrical portion 110 of the mounting plate 17
Has a fixed shaft 29 and a one-way meshing clutch 30 for restraining rotation in the counterclockwise direction.

Each of the pinions 12A to 12C of the drive shaft 4
Is set to a tip tip circle diameter having a gap between the tip of the rack tooth 10 and the other rack tooth 10 when the tip is engaged with the other rack tooth 10.

The cam plates 13A to 13D come into contact with the facing cam surfaces 11 of the slide frame 9, respectively, so that the movement trajectory of the rack teeth 10 of each slide frame 9 with respect to the pinions 12A to 12C cooperates with the rail portion 5. For example, as the moving distance of the cam plates 13A to 13D from the rotation center line of the driven case 2 increases, each of the rack teeth 1
0 by approximating and following the pitch circle of the large virtual internal gear centered on the rotation center line of the driven case 2, the gear ratio (radius ratio) between the drive gear 50 and the virtual pitch circle ) Can be decelerated.

The operation of the thus configured transmission 1 of this embodiment will be described. In order to start the stationary bicycle M, the user tries to rotate the pedal P of the bicycle M. As a result, the torque applied to the main sprocket from the crank arm is transmitted to the sprocket 4 via the chain C.
3 is transmitted.

The clockwise torque applied to the sprocket 43 causes the counter gear 21 meshing with the input cylinder 20 to rotate.
Presses the tooth surface of the drive gear 50 to rotate it clockwise. The numbers of teeth of the gear portion 45 of the input cylinder 20, the first and second gears of the counter gear 21, and the drive gear 50 are, for example, 28T, 20T, 16T, and 32T. 0.7 times, usually 0.5-0.
The speed has been reduced to about 9 times. This helps to generate a reaction force on the rotating frame 22 to prevent the rotating frame 22 from rotating clockwise.

On the other hand, a large load torque acts on the drive gear 50 when the bicycle M starts and when the bicycle M starts. Therefore, the counter gear 21 that attempts to rotate the drive gear 50 in the clockwise direction rotates around the pin 49 in the counterclockwise direction by the large reaction force from the drive gear 50 and rotates around the drive gear 50 together with the rotating frame 22. Attempts to revolve counterclockwise. However, as described above, the rotation frame 22 is prevented from rotating in the counterclockwise direction by the one-way dog clutch 30, so that the revolution of the counter gear 21 due to the rotation of the counter gear 21 is also prevented.

As a result, the load torque of the drive gear 50 is large, and the drive gear 50 cannot rotate sufficiently depending on the input torque of the second gear portion 52 of the counter gear 21.

However, due to the force applied to the drive gear 50 by the input torque of the counter gear 21, a rotational moment about the pin 49 is generated in the swing arm 23. When the rotational moment overcomes the urging force of the spring means 25, the swing arm 23 swings clockwise, and this swing causes the drive gear 50 to move through the receiving cylinder 54 of the swing arm 23 to the pin 49. Revolve around.

On the other hand, the drive shaft 4 includes the cam plates 13A and 13D having the bulges 92 extending vertically in the direction perpendicular to the drive shaft 4 as described above. Guide frame 100 of auxiliary plate 27 so that it can slide freely
And the guide frame 104 of the mounting plate 17.

Accordingly, the drive shaft 4 moves along the guide frames 100 and 104 from the initial state shown in FIG. 11 (a cross-sectional view seen from above in FIG. 1 and FIG. 12), and the rotation center of the driven case 2 The line CL and the shaft center of the drive shaft 4 move for the amount of eccentricity V (FIG. 12). As described above, the rotating frame 22
Is stopped by the one-way meshing clutch 30, and the displacement of the drive shaft 4 is accompanied by swinging about the boss 57 of the swing arm 23 (that is, centering on the pin 49).

Further, the swing of the swing arm 23 causes the engagement pin 56 to rotate the auxiliary plate 27, and as shown by a dashed line in FIG. 4, and as shown in FIGS. The orientation can be changed to assist the deflection of the drive shaft 4.

The displacement of the drive shaft 4 is controlled by the cam plate 13.
A, one arcuate surface 92 of the bulging portion 92 provided on 13D
B is limited by abutment with the arc segment 103.

The displacement of the drive shaft 4 is performed against the spring means 25 as described above. By the swing of the swing arm 23, the gear 24 formed at one end of the swing arm 23 rotates the meshing gear 66, and rotates the winding shaft 74 through the speed increasing portion 77. By pulling out the constone spring 26 from the winding case 82, the urging force, that is, the rotational force for restoring the initial state is applied to the sliding arm 23.

In addition, due to the start of rotation of the driven case 2 and the increase in the reduction ratio described below due to the swing of the swing arm 23, the load torque of the drive shaft 4 is reduced, and the drive force in meshing the drive gear 50 is reduced. In case, conston spring 2
The restoring force of No. 6 is increased by the speed increasing portion in accordance with the ratio and transmitted to the swing arm 23.

The oscillating arm 23 receiving the restoring force from the conston spring 26 reduces the load torque and gradually reduces the eccentric amount V of the drive shaft 4 to automatically reduce the reduction ratio. Return to the initial state of.

[0097] The deflection means 3 of the present embodiment operates as described above, so that a large load is applied to the driven case 2 such as when the bicycle M starts or climbs.
As shown in FIGS. 13 to 16, the drive shaft 4 is eccentric from the rotation center of the driven case 2 and increases the amount of eccentricity V.
After the start of the bicycle M, the amount of eccentricity V is reduced as the load on the driven case 2 is gradually reduced.
As shown in FIG. 20, the drive shaft 4 and the rotational center of the driven case 2 are made to coincide with each other, the eccentricity V is set to 0, and the speed ratio can be set to "1".

Next, the principle of shifting will be described. FIG.
Shows a state in which the drive shaft 4 is most eccentric separating the eccentric amount VM from the rotation center line CL of the driven case 2 by the cam 13. For example, one rack tooth 10 of the slide frame 9A meshes with the pinion 12A. At this time, the rack teeth 10
As described above, a virtual internal gear is formed by orbiting with the slide frame 9. At this time, the pitch circle diameter of the pinion 12 </ b> A is PD, and the center line CL is in contact with the pitch line of the rack teeth 10. , The pitch circle radius of the virtual internal gear is RM, the reduction ratio Rr between the drive shaft 4 and the slide frame 9, that is, the driven case 2 is: reduction ratio Rr = PD / 2 · RM And the load torque acting on the drive shaft 4 decreases in proportion to the reduction ratio.

The other rack tooth 10 of the slide frame 9A
When the driven case 2 is rotated by 180 °, the driven case 2 can be engaged with the pinion 12 </ b> A again to apply a rotational force to the driven case 2 as in this state.

FIG. 14 shows the slide frame 9B and the pinion 12B, and FIG. 15 shows the slide frame 9C and the pinion 1
FIG. 16 shows the relative relationship between 2C and 2C, and FIG. 16 shows a state in which these are superimposed by a virtual line.
The rack teeth 10 are arranged in the shape of an internal gear centered on the center line CL.

As apparent from these, each pair of rack teeth 10 can engage with each pinion every time the driven case 2 rotates 180 °. Further, in the present embodiment, the slide frames 9 are arranged so that their movement directions cross each other at 120 °. Therefore, when viewed as a whole, at least the rack teeth and the pinion mesh with each other while the driven case 2 rotates 60 °. However, one set is performed, and as a result, uneven rotation of the driven case 2 can be reduced and smooth rotation can be enabled.

The meshing between the pinion 12 and the rack teeth 10 is a repetition of meshing with one rack tooth and simultaneous meshing with two rack teeth. A smooth displacement of the shaft 4 is possible.

When the angle of intersection is set to 120 °, the rack teeth 10 and 10 have a C-shape. Therefore, even when the pinion 12 straddles the two rack teeth 10 and 10 and meshes with each other, the drive shaft 4 makes the movement smooth.

In particular, the rotation angle of the driven case 2 is approximately 60 ° from the start to the end of the engagement between the rack teeth 10 and the pinion 12.
By setting the contour of the cam plate 13 and the number of teeth of the rack teeth 10 so that
Engagement between the pair of rack teeth 10 and the pinion 12 can be always ensured, and smoother torque transmission can be achieved.

As described above, the rack teeth 10 can be moved along the oblique grooves 39 (FIG. 6) and the tip of the rack teeth 10 protrudes "inward" from the cam surface 11 ("0028") . By being urged, the impact at the time of starting engagement with the pinion and at the time of ending the engagement with the pinion can be mitigated by the backward movement as described above. Further, when two sets of the pinion and the rack teeth are engaged during the rotation of the driven case 2, and as shown in FIG. 20, the reduction ratio approaches 1, and the rack teeth 10 are projected in the rotation center direction. For example, when an overlapping portion occurs, the intersection between the two rack teeth 10 and 10 is a portion where the circumferential pitch of the teeth changes at the intersection. Easily move one rack tooth away from the pinion, such as when the pinion starts to mesh with such a part, to smoothly move from one rack tooth to the other and prevent kinking. Can. Furthermore, when stopping the petal and descending a slope, the rack teeth can escape to the stationary pinion, and can function as a ratchet.

Also, the grooves are arranged in the oblique grooves 39 (FIG. 6) in the predetermined direction.
By doing so, the transmission efficiency at the time of meshing is increased.

FIGS. 17 to 19 show arbitrary moments when the swing arm 23 returns due to the decrease in the load torque, and the rotation center of the pinion 12 approaches the rotation center line CL of the driven case 2 by the conston spring 26. Is shown, and one rack tooth 10 of the slide frame 9A is in mesh with the pinion 12A.

In this case, the slide frame 9A is guided by the cam plate 13 that is stationary, and moves the maximum stroke between the inward surfaces on one side and the other side of the driven case 2. At this time, since both the pinion 12 and the driven case 2 rotate integrally about the rotation center line CL, the speed ratio approaches “1”.

Further, when the load torque becomes zero and the counter gear 21 does not act on the counter gear,
Can rotate in the free rotation direction of the one-way dog clutch 30.

At this time, the movement of the slide frame 9 stops when the cam plate 13 also rotates by itself, particularly when the two rack teeth mesh with the pinion 12 in a C-shape.

In the case where there are six rack teeth as a whole in the present example, the number of teeth of the virtual internal gear to which the drive gear 50 can smoothly mesh is reduced by a multiple of six. Accordingly, when the number of teeth of the drive gear 50 is 24T and the number of teeth of the maximum pitch circle of the virtual internal gear is 48T, the speed ratio is as follows.

48:24 (1/2) 42:24 (1 / 1.75) 36:24 (1 / 1.5) 30:24 (1 / 1.25) 24:24 (1/1)

As described in detail above, the present invention is not limited to the above-described embodiment, but may be applied to motorcycles as well as bicycles.

[0096]

As described above, according to the transmission of the present invention, the amount of engagement between the rack teeth and the pinion is increased to reduce uneven rotation of the driven case, thereby enabling smooth transmission of torque.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention.

FIG. 2 is a sectional view showing one embodiment of the present invention.

FIG. 3 is a partial perspective view of one embodiment of the present invention.

FIG. 4 is a perspective view of a swing arm, an inner lid, and an auxiliary plate.

FIG. 5 is an exploded perspective view of a drive shaft.

FIG. 6 is an enlarged perspective view of a rail portion and a slide frame.

FIG. 7 is a perspective view illustrating an input cylinder.

FIG. 8 is a cross-sectional view for explaining a spring means.

FIG. 9 is a cross-sectional view for explaining a speed increasing section.

FIG. 10 is a diagram for explaining the contour of a cam plate.

FIG. 11 is a cross-sectional view for explaining displacement of a drive shaft.

FIG. 12 is a cross-sectional view for explaining displacement of a drive shaft.

FIG. 13 is a cross-sectional view illustrating a relative relationship between a drive shaft and a slide frame.

FIG. 14 is a sectional view showing a relative relationship between a drive shaft and a slide frame.

FIG. 15 is a cross-sectional view illustrating a relative relationship between a drive shaft and a slide frame.

FIG. 16 is a diagram for explaining a relationship between a pinion and rack teeth.

FIG. 17 is a cross-sectional view illustrating a relative relationship between a drive shaft and a slide frame.

FIG. 18 is a sectional view showing a relative relationship between a drive shaft and a slide frame.

FIG. 19 is a sectional view showing a relative relationship between a drive shaft and a slide frame.

FIG. 20 is a diagram for explaining a relationship between a pinion and rack teeth.

FIG. 21 is a diagram showing an embodiment in which the present invention is applied to a bicycle.

[Figure 22] Ah a perspective view for explaining a conventional transmission
You.

[Explanation of symbols]

 2 Drive Case 3 Deflection Means 4 Drive Shaft 5 Rail 6 Opening 7 Inner Side 9 Slide Frame 10 Rack Teeth 11 Cam Surface 12 Pinion 13 Cam Plate 14 Folded Piece 15 Linear Section 16 Arc Piece 17 Mounting Plate 19 Slot 20 Input cylinder 21 Counter gear 22 Rotating frame 23 Swing arm 24 Gear part 25 Spring means 26 Conston spring 27 Auxiliary plate 29 Fixed shaft 30 One-way meshing clutch 31 Spoke 32 Rear wheel M Bicycle

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F16H 35 / 00,19 / 04,29 / 16 B62M 11/06

Claims (1)

(57) [Claims] A driven case rotatably supported by a stationary member; a driven case disposed in parallel with a rotation center line of the driven case, and movably supported in a direction perpendicular to the rotation center line by using a displacement means. And a plurality of pairs of rail portions extending parallel to each other on both sides of the rotation center line and extending in a plane perpendicular to the rotation center line, and provided in the driven case, In addition, intersection lines parallel to the rails arranged in the direction of the rotation center line and intersecting with the rotation center line intersect with each other at an equal angle, and the rotation center line is guided between the facing rail portions by the rails. Slide frames each having an opening having two opposing inner sides are provided, and each of the opposing inner sides of the slide frame is provided with rack teeth and this rack. A cam surface parallel to the pitch line of the lock teeth is provided side by side; a pinion that rotates integrally with the drive shaft and meshes with the rack teeth on one inner side of the slide frame facing the slide frame; By guiding the slide frame by contacting the cam surfaces of the opposed inner pieces of the respective slide frames together, the rack teeth meshing with the pinion are moved along a locus that approximates a virtual internal gear pitch circle in which the rack teeth mesh with the pinion. A transmission plate having a cam plate to be moved, wherein the rail portion arranges three pairs in which the intersection lines intersect at an angle of 120 ° in a rotation center line direction, and the cam plate has an arc R1; Combination with an arc R2 having a larger radius than the arc R1 results in an omsby-shaped contour having the same length across the outer periphery, and the pinion is formed by the arc R1 of the cam plate. Transmission being characterized in that eccentrically to the radial center side.